Here is an anecdote for ya
I have a lynx 3d and was running my car from the drivers stand mayby 15-70 foot range required. Some idiot came in with one of those cheapo stick controllers on my frequency and started to run his electric car. He was MUCH closer to his car than I was. Except his car was the runaway not mine!!!!
Mine stayed under control. I run on the 29Mhz channel.
So I am sure that the more expensive transmitters have more "grunt" in the signal than the cheapo ones.